Self-filling fountain-pen



C. DUNN.

' SELF FILLING FOUNTAIN PEN.

APPLICATION FILED APR. 7, |917- RENEWED APR. 22, i920.

Patented Nov. 23,1920.

UNITED STATES `lafrla'r OFFICE CHARLES DUNN, or BROOKLYN, NEW YORK.

SELF-FILLING FOUNTAIN-PEN.

y Specification of Letters Patent. Patented NOV. 23, 1920.

Application led April 7, 1917, Serial No. 160,404. Renewed April 22, 1920. 'Serial No. 375,912.

T all fwhom t may concern Be 1t known that I, CHARLES DUNN, a

lcitizen of the .United States, residing at Brooklyn, in the county of Kings and State' of New York, have invented certain new and useful Improvements in Self-Filling F ountain-Pens, of which the following is a specification.

This invention relates to self filling foun-A tain pens, and the object of the invention is to provide such a pen which will be simple in constructionl and reliable in operation without valves or spring controlled parts.

A further object of the invention is to provide a pen in which successive reversals `of the direction of pressure on a supply pas- Fig. 4.

n Figs. 1 to 3 of the drawing, the invention is shown embodied in a self filling fountain pen of the plunger type in which the barrel or reservoir 1 is provided' with a solid en'd 2 at one end carrying the pen and the reciprocating plunger cylinder 3 at the other end. The solid end 2 carries the feed 23 and the pen 4 wedged in its bored central recess. The feed 23 is provided with alongitudinal supply passage or duct 5 leading from the pen point to the reservoir and with the air outlet 6 opening into the supply passage 5, from the air tubev 7 fitted centrally in the feed 23 to have its passage communicate with the outlet 6.

4When the pressure in reduced and the lower end of supply passage 5 is dipped into the ink the liquid will be drawn upinto the reservoir through the passage 5 rising sli htly also in tube l 7 through outlet 6.l ery little liquid will enter the tube 7 because of the small size of its passage and the sharp bends between passages 5, 6 and 7. Upon reversal of the operation will be communicated to the air column 1n tube 7 tending to discharge air through loosely within the reservoir the reservoir 1 isy the rise Of'pressure in reservoir 1l outlet6 and passage 5. The rise in pressure on the surface of the liquid in the reservoir also tends to drive the liquid directly out through passage 5, anda liquid outflow of suiiicient velocity through passage, 5 draws out the contents of outlet 6 andtube 7 by ejector action, carrying the air from tube out through passage 5. Thus, by the combined pressure within the tube 7 and the ejector action of any escaping liquid in passage 5, each rise in pressure within the reservoir 1 is accompanied by a discharge of some of the air within the reservoir and successive alternations of pressure and vacuum within the reservoir will fill it.-

In the plunger type of filler shown in Figs. 1 to 3, the variations in pressure within the reservoir 1 are brought about by the cylinder plunger 3 fitted in packing 8 of cork or similar material pressed between screw rings 9 and 10. At its outer end the cylinder carries the manipulating handle 11 locked in down position by screw threads 13; and at its inner end the cylinder is provided with an annular guiding ring orpiston 12. Reciprocation ofl this plunger 3 after unscrewing ofvthreads 13 will alternately enlarge and diminish the size of the reservoir and cause corresponding iiuctuations of pressure on the passage 5 and the tube 7 to fill the pen as above described.

In order to permit Vthe liquid to enter the space around the outside of plunger 3 and above the piston 12, this piston is fitted so that the ink or other liquid may pass around it when the reservoir is filled up to its level. This loose fit does not, however,` prevent the piston from having effective action in increasing the fluctuations of pressure within the reservoir for a given movement of the plunger 3 as at low levels of ink in the reservoir the liquid adhering to the piston will form a fairly tight airproof seal and when the ink reaches the piston 12 the dash-pot action of the ring in the liquid will serve to increase pressure on the down .stroke and increase the vacuum on the up stroke.

In the modified construction shown in Figs. 4 and 5, an internal tubing 15 of pli- I able material, such as soft rubber, is provided fastened at its outer end by a vflange 16 and an annular recess of a handle piece 17 yfitted to rotate in the Outer end of the barrel 1. The other end of the tubing 15 is caught between the wedge 18 of screw plug 2 and wedge walls 19 of the barrel 1. The

flange 16 is composed-of a series of knobs or corrugations 20' fitting into similar recesses in the handle piece 17 so that upon turning the handle 17 about its longitudlnal axis the upper end ofthe tubing 15 will turn with it. As the lower end of the tubing is held fast withthe barrel 1 the turning of the handle 17 from normal position shown in Fig. 4 will twist tubing 15 to collapsed or partially collapsed condition reducing the size of the reservoir within the barrel l and raising the pressure therein. Upon turning the handle or knob 17 in the reverse direction back to the normal expanded condition of tubing shown in Fig.

15, the size of the reservoir will be increased and the pressure therein decreased to draw in ink or other liquid through passage 5 into the reservoir and to some distance in air tube 7. Upon again rotating handle 17 to collapse the tubing 15 the pressure within the reservoir will be increased and force a small amount of fluid out through passage 5 and with it a quantity of air out of the reservoir through tube 7, outlet 6 and passage 5. By repeating back and forth rotation of the handle 17 the reservoir formed by the tubing 15 will be completely filled.

The passages 5, 6 and 7 assembled with the pen 4 are preferably capillary in nature, retaining any fiuid within from flowing out by gravitation alone. As the ink from the reservoir is used air will find its way back through passage 5 into the reservoir to allow the liquid to feed down. In order to empty the reservoir itis only necessary to alternate pressure and vacuum within the reservoir 1 in the same manner as for filling but keeping the end of passage 5 out of the liquid. [Upon depression of the plunger 3 or twisting of tubing 15 to raise the pressure in the reservoir, the liquid will be forced out through the passage -5 and upon raising plunger 3 or expanding the` tubing 15 airwill be drawn into passage 5 to replace the discharged liquid. And by repeating the process the reservoir can be en-` tirely emptied. v

No valves or spring pressed parts are used in the construction of the pen which is simple in structure and reliable in its operation. With each rise in pressure a maximum quantity of air is ejected and very little liquid as the air tube 7 is maintained substantially empty until the final filling stroke.l Each drop in pressure sucks a maximum amount of ink into the reservoir because the passage 5 is direct and free from resistance and very little liquid finds itsway into air tube 7. The reservoir 1 is completely filled by a few alternations of the pressure within it and there is no waste space leftl occupied by air.'

It is apparent that the arrangement, sizes and proportions of parts may be varied without departing from the principle of the invention which is not confined to the particular embodiments shown and described but is intended to cover such modications reservoir to the writing pen, an air tube permanently opening from a point in said passage to the opposite end of said reservoir, the resistance of said passage to the flow of fluid between said point and said reservoir being less than the resistance of said air tube thereto, and pressure varying means permanently in connection with said' reservoir for alternating the 'pressure therein above and below atmospheric pressure and adapted to produce a rise in pressure suiiicient to cause an outflow of air through said tube and feed passage so that said reservoir may be filled with ink by the alternations in pressure therein. l

2. In a self-filling fountain pen, the combination with an ink reservoir, of an ink feed passage permanently opening into said reservoir, an air tube permanently opening from a point in said passage tothe opposite end of said reservoir, the resistance of said passage to the flow of fluid between said point and said reservoir being less than the resistance of said air tube thereto, and pressure varying means permanently in connec tion with said reservoir for alternating the reservoir to permit ink to, pass between the piston and the reservoir wall and fill `the space around the plunger.

3. In a self-filling fountain pen, the com- Y' bination with an ink reservoir, of an unobstructed ink feed passage. permanently connecting one end of said reservoir to the .writing pen, an air tube permanently openat its inner ending from a point in said passage. to the opposite end of said reservoir,v a reciprocating plunger in said reservoir for alternating the pressure therein above and below atmospheric pressure and adapted to produce a rise in pressure sufficient to cause an outfiow of air through said tube and feed passage so that said reservoir may be filled with ink by the alternations in pressure therein without the intervention of valves or any constricted.

passage.

CHARLES DUNN. 

